*{
	margin: 0;
	padding: 0;
	box-sizing: border-box;
}
.built-in-app{
	width: 290px;
	margin: auto;
}
.built-in-app .nav > li{
	list-style: none;
	display: inline-block;
	position: relative;
	padding: 12px;
	cursor: pointer;
	font-size: 14px;
}
.built-in-app .nav li:hover{
	color: #F40;
}
.built-in-app .nav > .active{
	font-weight: 800;
	color: #3C3C3C;
}
.built-in-app .nav > .active::after{
	content: "";
	border-bottom: 2px solid #F40;
	width: 100%;
	position: absolute;
	left: 0;
	bottom: -1px;
}
.built-in-app .main > div{
	display: none;
}
.built-in-app .main > .active{
	display: block;
}
a{
	text-decoration: none;
}
.built-in-app .main a{
	width: 50%;
	height: 20px;
	overflow: hidden;
	    line-height: 25px;
	    font-size: 13px;
}
.built-in-app .main .left{
	float: left;
}
.built-in-app .main .right{
	float: right;
}
.built-in-app .main .a1{
	color: #ff5000;
}
.built-in-app .main .a2{
	color: #3C3C3C;
}
.built-in-app .main .a2:hover{
	color: #ff5000;
}